running under os x

I gave up and did the local install.  I ran 'isproxy' to set it up,
and upon running 'isproxy' for the second time, I get this output:

[Justin-Gomboss-Computer:~/src/iip-1.1.0/src] jgombos% ./isproxy
----------------------------------------------------------------------
[2003/04/04-05:06:46]:Logging at verbosity:2
[2003/04/04-05:06:46]:Starting internal tests...
[2003/04/04-05:06:46]:Tests passed.
[2003/04/04-05:06:46]:Retrieving node.ref
[2003/04/04-05:06:47]:Accepting IRC connections on port:6667
[2003/04/04-05:06:47]:Type /server localhost:6667 to connect, and then /join #anonymous
[2003/04/04-05:06:47]:Socket(5), Error (48):Failed to bind listening socket.
[2003/04/04-05:06:47]:sockListen: bind failed: host(127.0.0.1), port(6667)Failed to bind listening socket.

What am I doing wrong now?  I don't remember having this many problems
when I ran IRC years ago.